• 제목/요약/키워드: physicochemical water quality

검색결과 597건 처리시간 0.035초

다양한 전처리 방법에 따른 당근의 이화학 및 영양학적 특성 분석 (Effects of Various Pretreatment Methods on Physicochemical and Nutritional Properties of Carrot)

  • 김광일;황인국;유선미;민상기;최미정
    • 한국식품영양과학회지
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    • 제43권12호
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    • pp.1881-1888
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    • 2014
  • 본 연구는 당근을 열처리법 중에서 열수침지, 과열증기 및 볶음 처리에 따른 이화학적 및 영양학적 특성을 분석한 논문으로 열처리가 당근에 미치는 영향을 비교하고자 하였다. 상품을 구매할 때 1차적인 구매요소인 색도 및 경도 측정과 추가적으로 pH와 조직 관찰 결과로 최적 조건 선정 후 영양학적 및 관능검사를 실시하였다. 열처리를 하지 않은 대조구에 비해 짧은 시간의 열처리에서는 더 진하고 선명한 색을 띠었으나, 장시간 동안 처리한 열처리 시료는 색의 침착을 보였다. 원물과의 색은 열처리 후 차이를 나타냈지만 열수 및 과열증기 2분 처리까지가 원물과 가장 유사한 색을 나타냈으며, 경도는 열처리 시간에 따라 감소 경향을 나타냈고 볶음 처리는 짧은 시간으로도 물성이 연화됐으며, 열수침지 및 과열증기 처리는 2분까지 원물에 가까운 경도를 유지했으나 처리 시간이 길어질수록 경도가 확실히 감소하였다. 비타민, 유리당 및 유기산의 경우 열수침지 처리에서 가장 큰 손실을 보였고, 과열증기, 볶음 처리 순으로 손실된 결과를 보였다. 특히 유기산에서 succinic acid는 열수침지 처리 시 큰 손실률을 보이며 감소된 결과를 나타냈다. Peroxidase activity 변화는 열수침지 및 과열증기 처리에서 볶음 처리보다 높은 불활성화를 보였다. 당근의 열처리 조건은 과열증기 처리법으로 2분 동안 처리하는 것이 다른 처리법에서 처리한 시간들에 비해 최적으로 나타났다. 식품마다 열처리 방법 별 각각의 최적 처리 시간을 가지고 있어, 높은 효율성이나 산업적으로 이용하려면 최적의 전처리 방법과 처리 시간을 산정하는 것이 중요하다.

농업용 저수지 내 침강지의 설치유형에 따른 수질정화효율 평가 (The Evaluation of Pollutant Removal Efficiencies by Sedimentation Basin Types constructed at the Inlets of Irrigation Reservoirs)

  • 장정렬;최선화;남귀숙;권순국
    • 한국수자원학회논문집
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    • 제38권8호
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    • pp.665-674
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    • 2005
  • 본 연구의 목적은 농업용 저수지 유입부에 설치된 3가지 유형(준설형, 차수막형, 보조댐형)의 침강지에 대한 수질정화효율 평가와 수질정화효율 면에서 유리한 침강지의 유형과 적정규모를 살펴보는데 있다. 이를 위해서 주요 수질 항목에 대한 정화효율과 침강지 설치전후의 퇴적물의 이화학적특성을 조사하였다. 수질정화효율은 침강지 유형, 수질항목 및 조사시기에 따라 $-87\%$에서 $92\%$사이의 넓은 변동을 보였다. 농도회귀법(ROC)으로 평가한 설계정화효율은 준설형이 $18\%$, 차수막형이 $29\%$, 보조댐형이 $42\%$로 나타났다. 보조댐형에서는 퇴적물의 이화학적특성 변화가 있었으나, 다른 두 유형에서는 미미하였다. 정화효율, 배수면적 대 유역면적비(SAR), 체류시간 측면에서 비교한 결과, 보조댐형 침강지가 가장 유리한 것으로 나타났다. 따라서 침강지는 저수지 수체와 완전히 분리되는 구조이면서 SAR가 $0.7{\sim}1.0\%$ 정도인 규모가 적절하다. 

Effects of Aging and Aging Method on Physicochemical and Sensory Traits of Different Beef Cuts

  • Kim, Minsu;Choe, Juhui;Lee, Hyun Jung;Yoon, Yeongkwon;Yoon, Sungho;Jo, Cheorun
    • 한국축산식품학회지
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    • 제39권1호
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    • pp.54-64
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    • 2019
  • Wet and dry aging methods were applied to improve the quality of three different beef cuts (butt, rump, and sirloin) from Hanwoo cows (quality grade 2, approximately 50-mon-old). After 28 d of wet aging (vacuum packaged; temperature, $2{\pm}1^{\circ}C$) and dry aging (air velocity, 2-7 m/s; temperature, $1{\pm}1^{\circ}C$; humidity, $85{\pm}10%$), proximate composition, cooking loss, water holding capacity, shear force, color, nucleotides content, and sensory properties were compared with a non-aged control (2 d postmortem). Both wet and dry aging significantly increased the water holding capacity of the butt cuts. Dry aging in all beef cuts induced lower cooking loss than that in wet-aged cuts. Shear force of all beef cuts was decreased after both wet and dry aging and CIE $L^*$, $a^*$, and $b^*$ color values in butt and sirloin cuts were higher in both wet and dry aging (p<0.05) groups than those in the non-aged control. Regardless of the aging method used, inosine-5'-monophosphate content among beef cuts was the same. The sensory panel scored significantly higher values in tenderness, flavor, and overall acceptability for dry-aged beef regardless of the beef cuts tested compared to non- and wet-aged cuts. In addition, dry-aged beef resulted in similar overall acceptability among the different beef cuts, whereas that in wet-aged meat was significantly different by different beef cuts. In conclusion, both wet and dry aging improved the quality of different beef cuts; however, dry aging was more suitable for improving the quality of less preferred beef cuts.

Effect of Strawberry Puree on the Physicochemical Properties of Kochujang

  • Kim, Hui-Jeong;Seog, Eun-Ju;Lee, Jun-Ho
    • Preventive Nutrition and Food Science
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    • 제12권3호
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    • pp.185-189
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    • 2007
  • Quality characteristics of kochujang prepared with strawberry puree (10, 20, and 30% on the total weight basis) were investigated after 30 and 300 days of storage. The moisture content of strawberry kochujang at 300 days was considerably higher than that of strawberry kochujang at 30 days and increasing strawberry content from 0 to 30% significantly increased moisture content of kochujang progressively (p<0.05). Water activity and titratable acidity also showed similar trends, but pH showed the reverse trend with the highest value in control at 30 days and the lowest value in 30% strawberry kochujang at 300 days. As the strawberry puree content increased, amino-nitrogen content consistently and correspondingly decreased. Amino-nitrogen content at 300 days was higher than that of strawberry kochujang at 30 days. Soluble solids content also showed a similar trend, but soluble solid content at 300 days was considerably lower than that of strawberry kochujang at 30 days. Reduction in soluble solids content with increasing strawberry concentration was more evident at 30 days than at 300 day.

Evaluation of Cudrania tricuspidata Leaves on Antioxidant Activities and Physicochemical Properties of Pork Patties

  • Cuong, Tran Van;Chin, Koo Bok
    • 한국축산식품학회지
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    • 제38권5호
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    • pp.889-900
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    • 2018
  • Characterization and utilization of the bioactive compounds from natural resources is one of the most concerns to maintain quality properties of foods, especially to prevent the oxidation of lipids in meat products. Phytochemical components and antioxidant activities of Cudrania tricuspidata (CT) leaves extracted using various solvents and their effects on physicochemical properties of pork patties during refrigerated storage were measured. The combined solvents of 80% ethanol, 80% methanol and pure double-distilled (dd)-water obtained the higher total phenolic compounds, flavonoids content, and antioxidant activities as compared to the pure solvent alone. Among the individual antioxidant components, catechin was the predominant polyphenol in CT leaves in all extracts. The addition of CT leaves extracts into pork patties showed high antioxidant activities since thiobarbituric acid-reactive substances (TBARS) values of added CT extracts were lower than those of the control (p<0.05). In conclusion, CT leaf phytochemical components displayed antioxidant activity that varied with the extract solvent used. CT extracts were superior to control in retarding lipid oxidation of pork patties, which was evident as reduced TBARS and peroxide values (POV).

한우 $1^+$ 등급육의 이화학적 특성과 기호성에 관한 연구 (A Study on the physicochemical Properties and Palatability of Hanwoo Beef Loin in $1^+$ Grade)

  • 문윤희;김미숙;김대진;양종범;강세주
    • 한국식품영양과학회지
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    • 제28권6호
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    • pp.1288-1292
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    • 1999
  • The physicochemical properties and palatability of Hanwoo(cow, steer, and bull) beef loin(1+ carcass grade) were studied. pH(5.56~5.69), moisture content(67.6~69.0%), crude protein content(17.8~18.7%), and crude fat content(11.9~13.8%) of Hanwoo beef loin did not show significant difference between the types of Hanwoo. L(44.5~46.9), a(19.9~20.6), and b(10.3~11.6) color parameters, water holding capacity (69.4~70.5%), volatile basic nitrogen content(9.86~11.28mg%), thiobarbituric acid value(0.148~0.158 mg malonaldehyde/kg), and cooking loss(26.3~27.9%) of beef loin did not show significant difference between the types of Hanwoo either. Hardness, myofibrillar fragmentation index(MFI), and chewiness of beef loin were 6.1~6.9 dyne/cm2, 50.3~54.9, and 39.5~ 52.0g, respectively. No differences were found in hardness and MFI between the types of Hanwoo, while chewiness of cow was much lower than that of steer and bull(p<0.05). Cow was the best in palatability.

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Influence of the pH and Salt Concentrations on Physicochemical Properties of Pork Myofibrillar Protein Gels Added with Cornstarch

  • Lee, Chang Hoon;Chin, Koo Bok
    • 한국축산식품학회지
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    • 제40권2호
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    • pp.254-261
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    • 2020
  • The aim of this study was to evaluate quality characteristics of pork myofibrillar protein (MP) added with cornstarch as affected by different pH values and salt cocnentrations. MP mixtures were prepared with three different pH values (pH 6.00, 6.25, and 6.50) and three different salt concentrations (0.15, 0.30, and 0.45 M). Cooking yield (CY), gel strength, viscosity, and scanning electron microscopy were measured to evaluate characteristics of MPs. CYs of MPs with cornstarch at above pH 6.25 or salt 0.30 M were increased compared to those at pH 6.00 or salt 0.15 M. However, gel strengths of MPs at salt 0.45 M were higher than those at salt 0.30 M. In microstructure analysis, MP gels with increasing pH value and salt concentration showed compact and uniform structure. Thus, MP gels with pH 6.25 and salt concentration of 0.30 M would be better for manufacturing meat products containing cornstarch to increase their water holding ability.

식이섬유 첨가에 의한 백설기의 특성변화에 관한 연구 (Effect of Addition of Dietary Fibers on Quality of Backsulgies)

  • 최인자;김영아
    • 한국식품조리과학회지
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    • 제8권3호
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    • pp.281-289
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    • 1992
  • The physicochemical, rheological and sensory characteristics of Backsulgies added with dietary fibers-cellulose, pectin and wheat bran-were investigated. The maximum acceptable ratio of fibers was 10% for wheat bran or cellulose, 3% for pectin. As me results of physicochemical analysis, cellulose and pectin had larger water-binding capacity man wheat bran. Swelling power was increased with temperature increment. But the type of added dietary fiber did not make significant differences. The degree of gelatinization was measured by maltose content. The retrogradation of backsulgies was significantly delayed by the addition of dietary fibers. The retardation effect of dietary fibers for retrogradation of backsulgies was also proved by textural analysis and time constant determination of Avrami equation. Pectin had especially excellent delaying effect while me storage time extended. There were no significant differences in sensory characteristics between me backsulgi with no dietary fibers and backsulgies added with cellulose 3%, pectin 1% and wheat bran 3%. Therefore, we concluded mat cellulose 3%, pectin 1% and wheat bran 3% were me optimum addition ratios, which have the delaying effect of retrogradation, and which could be accepted as same as conventional backsulgies organoreptically.

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가로림연안 수질환경의 특성과 장기변동 (Long-term Variation and Characteristics of Water Quality in the Garolim Coastal Areas of Yellow Sea, Korea)

  • 박승윤;김형철;김평중;박경수;고준영;전상백;이승민;박종수
    • 해양환경안전학회지
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    • 제15권4호
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    • pp.315-328
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    • 2009
  • 1997년부터 2008년까지 12년 동안 가로림연안 수질환경의 특성과 장기변동 경향을 조사하였다. 3개 조사정점에서 수층(표층, 저층)별 및 계절별로 년 4회 수온, 염분, 부유물질, 화학적산소요구량, 용존산소, 영양염류, 클로로필 a에 대해 조사한 결과, 표층수와 저층수 간에 수온을 제외한 진조사항목에서 표 저층간의 차이가 없었다. 공간적 분포특성은 모든 조사항목에서 정점간 유의적인 차이가 없어 가로림만 중간부터 외측으로 원활한 해수교환이 이루어지고 있었다. 계절별로는 수소이온농도와 암모니아질소을 제외한 조사 항목에서는 유의성이 입증되었고, 정점별로 대체로 비슷한 변화폭을 나타내었다. 12년 동안 수질의 장기 변동은 네 그룹으로 구분되어 항목에 따라 부분적으로 차이가 있으나 전반적 장기 변동을 조사한 결과 근래에 들어 염분은 높아진 반면, 용존무기질소, 질산질소 및 화학적산소요구량 등이 감소하고 있어 담수의 유입이 거의 없는 대체로 양호한 수질상태를 유지하고 있으며 수산학적으로 매우 중요한 연안으로 앞으로 지속적인 보전이 요구된다.

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Meat Quality of Loin and Top Round Muscles from the Hanwoo and Holstein Veal Calves

  • Yim, Dong-Gyun;Chung, Eui-Gang;Chung, Ku-Young
    • 한국축산식품학회지
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    • 제35권6호
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    • pp.731-737
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    • 2015
  • This study was conducted to compare the meat qualities of loin (m. longissimus dorsi) and top round (m. semimembranosus) from Hanwoo and Holstein veal. Ten Hanwoo and Holstein calves were randomly selected from a local cattle farm and raised. They were slaughtered when they were 8 mon old and weighed. Weight and percentage in primal cuts and slaughter performance of Hanwoo and Holstein veal calves are obtained. Immediately after weighting, slices of loin and top round muscles were sampled. After vacuum packaging, the samples were subjected to proximate composition, physicochemical and microbiological analyses. Dressing weight and percentage were heavier and greater (p<0.05) in the Holstein than in the Hanwoo. Water contents of the top round muscle was higher in the Holstein than in the Hanwoo (p<0.05). Water-holding capacity, protein content and CIE L* (lightness) of both muscles were higher in the Holstein than in the Hanwoo veal, whereas fat content, pH, cooking loss, a* (redness), and b* (yellowness) were higher in the Hanwoo than in the Holstein veal (p<0.05). Thiobarbituric acid and volatile basic nitrogen values of both the muscles were lower in the Hanwoo than in the Holstein veal during the first 10 d of storage (p<0.05).